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Actually, it's likely that may be normal.
Cell signals are not uniform, several factors come into play. The further you are from a tower, the lower the signal. The idea is that before you lose the signal altogether, you get a better signal from the next tower over. That's the theory, and it's mostly true.
However, the signal can be degraded by several things:
- signal interference
- this can come from physical obstructions, like hills
- multiple tower signals can meet in certain spots and instead of getting more signal, they cancel out and you get less
- cell tower electronics not working right
To see what might be going on in your case, I recommend (and use myself) Open Signal Maps, it's free in the Market. Run that app, give it a half minute, then go to the maps tab - see if your phone is just locking in to one tower near you, or is it swapping back and forth between towers. And also see, using the info button (i) on the main page, it may be able to give you the distance to the tower you are using.
Post your results back here, and if you don't mind, I'm going to move our chat from the more social Lounge to our Android Lounge.
We have a forum just for your phone model, but I think your question is of interest to the whole Android community.
